The company’s new plan is built around four separate features called Circles, Sparks, Hangout and Huddle. Google is keen to stress that the new products do not form a new, single social network that rivals Facebook, but it is the search giant’s most serious attempt to incorporate social elements into its products to date.

Writing on the Google blog, senior vice president of engineering Vic Goduntra said that “Today, the connections between people increasingly happen online. Yet the subtlety and substance of real-world interactions are lost in the rigidness of our online tools. In this basic, human way, online sharing is awkward. Even broken. And we aim to fix it.”

Initially, Google is conducting a ‘field trial’, inviting select journalists, bloggers and other organisations, and it has not said when the products will launch more widely.

Circles is the closest product to Facebook; it allows users to drag in contacts to individual groups. The aim is to allow people to share different things with different groups of people more easily. Google users will be able to add their contacts, or import them from Yahoo or Microsoft. Facebook does not permit the export of contact information to Google.

Sparks lets users share content from around the web, and suggests more content. The company calls it a ‘sharing engine’, like a search engine. Goduntra writes “Thanks to Google’s web expertise, Sparks delivers a feed of highly contagious content from across the Internet. On any topic you want, in over 40 languages. Simply add your interests, and you’ll always have something to watch, read and share”.

Hangout encourages users to share content within groups, being able to watch a YouTube video together, at the same time, despite not being in the same room. Goduntra likened it to a shared space, such as a pub, or a chance conversation with a neighbour.

Huddle is a group messaging application, that combines allows messages to be sent to large numbers of people, and is aimed at groups trying to, for instance, organise a night out.

The new services can be used via a new toolbar that Google is rolling out, aimed at encouraging people to share their status as they would via Facebook. Mobile elements also work with Android phones and Apple’s iPhone. The company has also introduced a new feature that immediately uploads photos and videos taken with Android devices. If users wish, any update can also be tagged with a location.

Initial reaction online to Google+ was either mixed or positive, largely because users have had little opportunity to try out the new services. Search Engine Land wrote that “As for a wider release, and possible success, it’s anyone’s guess. If you’re happy using Facebook, there seems relatively little to make you want to switch over to Google Plus, at the moment. Perhaps with further Google +1 integration, that might change. Perhaps if there are people who want a Facebook alternative, Google’s now got a core to build on for them.”

Technology blog TechCrunch said that “As it is unveiled to the world, Google+ sounds and looks great. But we’ve seen that before from Google. Now comes the hard part.”